Attention: TDR Forum Junkies 
OK, I've pondered.
Obviously there is a problem. A small floater (dirt, rust, rubber... ) can cause a relief valve to hang. Burs or scratches on the components of the valves can hang when they heat up.
The other possibility that I can come up with is the VP for what ever reason is dumping fuel into the (for lack of a better description) fuel rail in the head. There is not pressure relief on the return side of the injectors. I'd almost be tempted to check the flow coming out there. Problem being that if this is the case, the VP delivery valves (I forgot the correct term for the internal components of the rotary pumps) and the injectors are passing charge pressure directly into the return. This would be a catastrophic failure that should be apparent in driveability.
Barry, since no one has come up with any other ideas, I may need to come down and help you with this. I am to the point where we may need to rig up an isolated fuel delivery system to your engine, and have the current transfer pump run straight through a regulator to see if we can isolate the problem to the VP side, or the transfer pump side.
I will also dig into my CMP leavin's to see if I have an extra return valve for the VP. May still have my last one from my VP replacement.
I will continue to ferment on this, and a re-read of the thread to date. Might be something I am missing, or need to ask.
Obviously there is a problem. A small floater (dirt, rust, rubber... ) can cause a relief valve to hang. Burs or scratches on the components of the valves can hang when they heat up.
The other possibility that I can come up with is the VP for what ever reason is dumping fuel into the (for lack of a better description) fuel rail in the head. There is not pressure relief on the return side of the injectors. I'd almost be tempted to check the flow coming out there. Problem being that if this is the case, the VP delivery valves (I forgot the correct term for the internal components of the rotary pumps) and the injectors are passing charge pressure directly into the return. This would be a catastrophic failure that should be apparent in driveability.
Barry, since no one has come up with any other ideas, I may need to come down and help you with this. I am to the point where we may need to rig up an isolated fuel delivery system to your engine, and have the current transfer pump run straight through a regulator to see if we can isolate the problem to the VP side, or the transfer pump side.
I will also dig into my CMP leavin's to see if I have an extra return valve for the VP. May still have my last one from my VP replacement.
I will continue to ferment on this, and a re-read of the thread to date. Might be something I am missing, or need to ask.
